#Denver was drier than #Phoenix in 2018

Denver received only 8.53 inches of precipitation (rain and snow-equivalent rainfall) in 2018, making it the sixth-driest year in the city’s recorded history. That’s a striking number for a bunch of reasons, but the main one is that it’s less than 60 percent of Denver’s average annual precipitation of 14.30 inches.

Here’s another way to think about it: Denver saw less rain in 2018 than true desert climates like Phoenix and Tucson, and Denver saw a rain total closer to America’s driest major city, Las Vegas (4.19 inches) than our average annual rainfall. Denver saw about 12 percent of Atlanta’s annual precipitation, 13 percent of New York’s and 17 percent of Chicago’s…

…only two months last year produced above-average moisture (January and March). The worst of the drought came in June (22 percent of average rainfall), July (48 percent), August (55 percent) and September (19 percent).

Why did 2018 lean on the drier side? When you’re measuring a full year’s worth of moisture, there are several factors to consider, but one thing stands out: an exceptionally dry late spring and summer, which is usually Denver’s wettest season. Summer storms usually help soak the ground. Droughts are often exacerbated by a positive-feedback loop, meaning dry soils and a lack of moisture in the air can suppress future rain and snow chances.

There was also a striking lack of snowfall in Denver for the second consecutive winter. DIA and Stapleton recorded less than half of Denver’s typical annual snowfall of about 57 inches. After the 2016-’17 winter produced the second-lowest snow total in Denver’s recorded history, the 25.7 inches DIA registered in 2018 was a slight improvement, amounting to the fifth-lowest snow total in the city’s recorded history.